Mounting for sewing-machine motors



June 21, 1921. 63 ,795

H. MAIMIN MOUNTIN FOR SEWING MACHINE MOTORS Filed Dec. 10. 1925 2 Shanta-Sheet 1 INVENTOR ATTORNEY3 June I l 9 H. MAIMIN MOUNTING FOR SEWING MACHINE MOTORS 2 Sheets-Sheet 2 Filed Dec. 10, 1925 INVENTOR I; ATTORNEY Patented June 21, 1927.

UNITED STATES PATENT QFFICE.

HYMAN MAIMIN, on new YORK, n. Y., assrenon T0 Mariarnsrnnn con'frnor. con- PORATION, A CORPORATION or NEW YORK.

MOUNTING non SEWINGTMACHINE Morons.

Apphcation filed December 10, 1925. Serial No. 74,494.

the drive on a domestic sewing machine is notsosimple. Such a mounting should-be readily secured to all types of hand or footoperated domestic sewing machines without the use of screws, bolts or other'fastening means requiring the services of a mechanic and defacing the machine or its stand. It should be readily removable to permit closing or covering of the machine and yet hold the motor securely in position during use. It is an object of the present invention to provide such amounting, particularly adapted for use in connection with domestic-machines.

'The speed of the sewing machine must be under control and this control is commonly "effected by varying thespeed of the motor by means of a rheostat. The use of rheos'tats is objectionable for several reasons; they are expensive, they getout of order easily, and they do not, for the most "part,

give a smooth curve variation in-the speed of the motor. I prefer to vary the speed of the machine, not by varyingthespeed of the motor held in fixed dr ving relatlon to the machine, but by varying the drivlng pressure between the motor and the machine while running the motor at constant speed. This variation in the driving pressure is effected by a controlled bodily movement of the motor relative to the machine. Then the drive is a friction drive, the functional contact between the driving pulley of the motor and the hand-wheel of the machine 'is varied, and where the drive is-a' belt drive, thetension on the beltis'varied. In order to limit theanaximum driving pressure it has been proposed to employ'the weight of the motor itself for exerting this pressure. This is commonly known as the gravity con- 'trol illustrated in my Patent'No,

1,377,018 wherein is described a motor drive for sewing machines in which a motorrunning continuously at a constant speed is mounted. adjacent the machine and constantly urged into driving relation by means oi? its own weight. This movement, however, is opposed by means of a spring which normally holds the motor in inoperative position and the force 0t which must be counteracted by the operator to permit the motor to move under its own weight into driving position. The eil'ective driving pressure'of the motor and hence thespeed of thesewing machine can thus be nicely and easily controlled. It is a more specific object of the present in'vention'to pr'ovi'dea" motor mounting suitable for a drive in whichthe speed ofthe machine is varied by varying the driving pressure of the motor and particularly adapted for a gravity control drive.

In attaining these objects I have mounted. the motor upon a'bracket' intended itobe suspended tromthe frame of the machine, making use of one of the small openings commonlyiound in the rear wall'of'the vertical arm of the machine frame and utilized armbelow the opening,the momenttexer-ted by the 'wei'gh't'ot the motor'holding the bracket inposition. The motor-isnroved into driving relation with the machine by means of its own weight,- but is'normally held out or driving-relation by means of a spring under the'control of the-operator.

- In the accompanying i d awings' I have illustrated a preferred embodiment of my invention. In these drawings Figure 1 is a sideele'vation-ot the right handend of a sewing machine showing a driving motor 'mounted adjacent thehand-wheel in accordance with the present invention; Figure 2 is a vertical section taken along line 2-2 of Figure 1;Figure 3 is'a vertical section taken along 'line '33 of Figure 1 and *Figure 4' is a horizontal section taken along line H of Figure 1. The'sewing machine illustrated'in the drawings 'comprises' the usual frame 1 having a horizontal arm 2 and avertical arm 3 extending upward'from the table or stand 4. The machine is provided with the ust' alhand-wheel 5 journaled Within'the frame. Therear'wall. of'the vertical arm 3 is provided with a plurality of openings 6 permitting access to the inte rior oi. the frame and utilized in assembling the machine. I shall now describe the means by which I mount a drivingmotorin operative relation to the machine.

The motor 7 is arranged with its shaft in a plane with the axis of the rotation of the hand-wheel and generally parallel thereto and with its cone-shaped driving pulley 8' just below the hand-wheel. This motor is pivotally mounted at 9 upon a supporting bracket 10 provided with a yoke member 12 which directly supports the motor and to which the motor is pivotally connected. This yoke member is mounted for vertical adjustment upon a horizontal arm .13 of a thrust the lower peripheral edge thereof. The moment exerted by the weight of the motor holds the thrust member and the hooked arm i in the positions illustrated in the drawings and thus firmly anchors the motor itself in driving relation to the machine. I shall now describe the manner in which the speed of the sewing machine is controlled by the motor mounted as described above.

Secured to the lower part of the motor housing is a cylindrical casing 18 which.

houses a compression coil spring 19. The inner end of this coil spring bears against a cap 21 and the outer. end against a movable plunger 22 which in turn bears against a depending car 23 on the bracket. The spring is so designed that acting through the plunger 22 and the ear 23,-it opposes the weight of the motor and normally holds it tilted about its pivot in the position illustrated in full lines in the drawing, the driving pulley 1 being thus held out of contact with the handwheel as shown. In order to permit the mo-' for to swing downward about'its pivot and move the driving pulley into contact with the hand-wheel it is necessary to compress the spring. This is doneby means ofa Bowden wire 23 under the control of the operator. This Bowden wire comprises the usual casing 25 and inner wire 26. The upper end of the wire 26 is secured to the plunger 22 and the lower end to a treadle 27. The operator by pressingthe outer end of the treadle downward exerts a pull on the wire 26 which, acting through the plunger 22, compresses thespring 19, thus overcoming the effectiveness of that spring andpermitting the motor to swing its driving pulley "into contact with the hand-wheel. The driving pressure exerted by the'driving pulley against the hand-wheel can thus be concreases this contact may develop into a small area, but the increase in the effective driving )ressure is constant. VVith the rooved ulley this might not be the case.

The motor drive illustrated and described above is readily positionedrelative to the machine by the simple expedient'ot inserting the hooked end 17 otIthe bracket into one of the openings 6 and swinging the thrnstniel'nher into contact with the vertical wall of arm 3. No other securing means are'neces sary, the weight of the motorholding the bracket securely in place. drive can be accomplished quickly and easily. Employing the gravity control principle, the motor can be swung into and out of driving relation to the hand-wheel without in any way interfering with the supporting bracket.

' I claim:

1. In a sewing machine having a frame with an opening therein, the combination of a motor support having an arcuate thrust member bearing against the frame, and a vertical arm secured to the support, and

Removal of the l having a hook entering theopening in the 7 frame above the thrust member for holding the support suspended upon the frame.

2. In a sewing machine having a handwheel and a frame with an opening therein, the combination of a motor support having an arcuate thrust member bearing against the frame, a vertical arm secured to the thrust member, and having a hook entering the opening in the frame above thethrust member for holding the support suspended upon, the head, and a motor on thesupport,

the weight of the motor holding the thrust member and the hook final in position.

3. In a sewing machine aving a frame with an opening therein, the combination of a motor support having an arcuate thrust member bearing against the frame, a vertical arm secured to the thrust member, and having a hook entering the opening in the frame above the thrust member for holding the support suspended upon. the frame, a motor plvotally mounted on the support, and a driving pulley on the motor contacting with the lower part of the hand wheel.

I 4. In a sewing machine having a frame with an opening therein, the-combination of a motor support having an arcuate thrust member bearing against the frame, a vertical arm secured to the thrust member, and having a hook entering the opening "in the frame above the thrust member for holding the support suspended upon the frame, a

motor pivotally mounted on the support, a

driving pulley on the motor contacting with the lower part of the hand-wheel, and means 7 for swinging the'motor about its pivot to vary the pressure of the driving pulley against the hand-wheel.

5. A sewing machine comprising the combination of a frame having a horizontal and a vertical arm, a hand-wheel, an opening in the vertical arm facing the hand-wheel, a motor supporting bracket suspended from the opening in the vertical arm having a thrust member bearing against the vertical arm below the opening, and a motor mounted on the bracket with its center of gravity beyond the thrust member on the side away from the frame, so that the weight of the motor holds the thrust member against the'vertical arm.

6. A sewing machine comprising the combination of a frame having a horizontal and a vertical arm, a hand-wheel, an opening in the vertical arm facing the hand-wheel, a motor supporting bracket suspended from having a frame and a hand-wheel comprising the combination of a motor supporting bracket, means for suspending the bracket from the frame of the machine, a motor pivotally mounted on the bracket with its driv-- ing pulley adjacent the hand-wheel and urged into contact therewith by the weight of the motor, a spring carried by the motor bearing against the bracket and normally tilting the motor so that its driving pulley is out of contact with the hand-wheel, and means under the control of the operator for counteracting the effect of the spring.

In testimony whereof I affix my signature.

,HYMAN MAIMIN. 

